Answer:
9.5 seconds
Explanation:
You need to make the ending speed into meters per sec.
So it would be 120km/h = 33.33m/s
If the acceleration rate is 3.5m/s, then the final answer would equal to 9.5 seconds
Also btw rounding it up is a good idea too so 10 seconds if you round
Answer:
B. Electrons are transferred from the fur to the plastic rod.
Explanation:
Triboelectricity or friction charging refers to the ability of materials to gain or lose electrons as a result of rubbing them against something. This phenomenon has been observed in the case of rubbing plastic rod against fur, or glass rod against silk.
In the context of rubbing plastic rod against fur, what happens is that the fur which has an excess of charges loses electrons to the plastic rod. This makes the plastic rod to become positively charged, and the fur, negatively charged.
Answer:
The maximum static frictional force is 40N.
Explanation:
When an object of mass M is on a surface with a coefficient of static friction μ, there is a minimum force that you need to apply to the object in order to "break" the coefficient of static friction and be able to move the object (Called the threshold of motion, once the object is moving we have a coefficient of kinetic friction, which is smaller than the one for static friction).
This coefficient defines the maximum static friction force that we can have.
So if we apply a small force and we start to increase it, the static frictional force will be equal to our force until it reaches its maximum, and then we can move the object and now we will have frictional force.
In this case, we know that we apply a force of 40N and the object just starts to move.
Then we can assume that we are just at the point of transition between static frictional force and kinetic frictional force (the threshold of motion), thus, 40 N is the maximum of the static frictional force.